The Doctor, Adric, Nyssa and Tegan find themselves in 1925 England,
where through a case of mistaken identity they become involved in a
charity cricket match at Cranleigh Halt. There, Nyssa discovers that
Charles Cranleigh's fiancee, Ann Talbot, is her exact double. The
Cranleighs harbour a dark family secret, however: a hideous monster
hidden in a secret wing of their house. Fixated on Ann, it breaks out
during a costume ball and attempts to kidnap her... but takes Nyssa by
mistake.

Production

For Doctor Who's eighteenth season, producer John Nathan-Turner
had secured a budget for twenty-eight episodes -- two more than had
previously been the norm. This meant that the year could consist solely
of four-part stories, rather than incorporating a six-episode adventure
as had been the tradition since the mid-Seventies; Nathan-Turner felt
that serials of this length were no longer viable. Season Nineteen was
originally planned to follow this format as well. Around the start of
1981, however, Nathan-Turner decided to use two of the episodes
allocated to Season Nineteen to make a one-hour pilot for a proposed
spin-off series, called K·9 And Company. This meant that he would
now require a two-part story for Doctor Who -- the first time an
adventure of this length had appeared in the programme's schedule since
The Sontaran Experiment in 1975.

In February, script problems with “Project Zeta-Sigma”,
intended to be the premiere story for Season Nineteen, threw the
Doctor Who production schedule into chaos. Fortunately, Terence
Dudley had written his scripts for Four To
Doomsday very quickly, meaning that it could be slotted into the
recording order in place of “Project Zeta-Sigma”. As a way
of thanking Dudley, Nathan-Turner decided to commission from him a
two-part story called “The Beast”. Dudley had previously
discussed this idea with former script editor Christopher H Bidmead
around August 1980. At the time, Bidmead had been unimpressed with the
notion of an Agatha Christie-style murder mystery because it did not fit
the mold of strong, science-based storylines that he and Nathan-Turner
wanted for Doctor Who.

Black Orchid was the first
Doctor Who story without any science-fiction
trappings since 1967

Nathan-Turner disliked Dudley's original title for his serial, so by
February 9th, when formal permission was sought for Dudley to write the
scripts, “The Beast” had become Black Orchid.
Nathan-Turner liked the fact that Black Orchid (now designated
Serial 6A) would put Nyssa in the spotlight; other Season Nineteen
stories were already focussing on her fellow companions (Tegan in Kinda and Adric in “The Enemy
Within”, later replaced by Earthshock) and with so many regular
characters, the producer felt that this would help the audience relate
to each one. He was also keen on the fact that Black Orchid would
be the first Doctor Who story without any science-fiction
trappings at all since The Highlanders in
1967.

No Doctor Who producer had directed an episode of the programme
since Barry Letts in the early Seventies. Nathan-Turner contemplated
bucking this trend and directing Black Orchid himself, but by the
summer his work on the remainder of the season, as well as K·9 And
Company, precluded this. John Black -- who had just completed Four To Doomsday -- was then considered.
However, Black was also assigned to direct K·9 And Company, and
since this would go into production soon after Black Orchid was
recorded, it was agreed that he could not feasibly helm both
stories.

Instead, Nathan-Turner decided that, given its brevity, Black
Orchid would be a good serial to assign to a novice director. Until
becoming Doctor Who's producer, Nathan-Turner had worked as a
production unit manager, and he was aware that one of his colleagues,
Ron Jones, had recently completed the BBC's internal directors course.
Jones had briefly worked in radio before moving into television as an
assistant floor manager, and had directed some segments for Blue
Peter. Black Orchid would be his first proper credit as a
director.

The story which preceded Black Orchid into production was Castrovalva, and much of its location filming
had taken place on the grounds of Buckhurst Park in Withyam, East
Sussex. The cast and crew had been warmly welcomed by the estate's
owner, Earl De La Warr, and so in late September, Nathan-Turner
approached the Earl about using the main residence as Dalton Hall. The
Earl was less eager to feature the house itself in Doctor Who,
but ultimately consented on the condition that personal photography was
strictly controlled.

Sarah Sutton was disappointed that Vanessa Paine, her
double as Nyssa and Ann, did not resemble her more closely

First, however, Jones' team spent October 5th at Quainton in
Buckinghamshire. The roadway material was filmed on Quainton Road, while
the police station was actually an abandoned house on the same
thoroughfare. Cranleigh Halt was in fact the Quainton Road Railway
Station. Although Jones planned his shots to keep Nyssa and Ann Talbot
from appearing together as much as possible, this was not always
feasible. Vanessa Paine was therefore hired to double as either Nyssa or
Ann depending on the requirements of the shot. Sarah Sutton was
disappointed that the actress did not resemble her more closely.

The next four days were then spent at Buckhurst Park. On October 6th,
the stunt in which George Cranleigh plummets off the roof went awry,
with stuntman Gareth Milne missing his cushioned target and striking the
ground with his legs. Fortunately, Milne was not hurt in the incident.
Sutton and Janet Fielding were delighted to take part in the dance
sequences, filmed on the 7th and 8th. Matthew Waterhouse was less
enthusiastic, and suggested that Adric should be more interested in
the food so that he would not have to participate in the
choreography.

Black Orchid was accorded just two studio days: October 20th and
21st, in BBC Television Centre Studio 3. The first day dealt with all of
the material in the TARDIS, Nyssa and Tegan's guest bedroom, the secret
corridor and the small annexe, along with some scenes in the drawing
room, George's cell, and the landing. These were completed on the 21st,
together with sequences on the stairs, in the Doctor's guest bedroom,
and in Ann's room. Unfortunately, taping on this day was badly delayed
due to an industrial dispute by the electricians' union. Although Jones
worked quickly and Nathan-Turner authorised a costly one-hour overrun,
two scenes in Ann's bedroom, in which she is covertly watched by George,
had to be abandoned. Jones subsequently tried to repair the damage by
using shots of George which had been recorded the previous day.
Nonetheless, Nathan-Turner was impressed by how Jones had handled such
difficult circumstances, and immediately hired him to helm the season
finale, Time-Flight, which had just lost
its intended director.